Patent application title: Branched Stent Delivery System

Abstract:

An interventional delivery system with a first catheter having at its
distal end a side branch vessel segment; a second catheter attached
around the first catheter and having at its distal end a main vessel
segment; a side branch vessel device attached to side branch vessel
segment of the first catheter; and main vessel device attached to the
main vessel segment of the second catheter. The main vessel device and
the side branch vessel device are able to be simultaneously delivered to
a treatment site.

Claims:

1-23. (canceled)

24. A first catheter assembly comprising:a catheter having a shaft and a
reverse facing segment;a connection means to join said shaft and reverse
facing segment; anda side branch device positioned onto the reverse
facing segment.

25. A first catheter assembly comprising:a catheter having a shaft and a
reverse facing segment;a side branch device positioned onto the reverse
facing segment;a connection means to join said shaft and reverse facing
segment; andan apex formed by the open end of the shaft and open end of
the reverse facing segment to allow a bifurcated guidewire to move freely
within the catheter.

26. The first catheter assembly of claim 24 wherein the shaft and the
reverse segment are comprised of different materials.

27. The first catheter assembly of claim 24 wherein the shaft and the
reverse facing segment each have one or more openings near the connection
means.

28. The first catheter assembly of claim 24, wherein the shaft has a first
opening and a second opening and the reverse facing segment has a first
opening and second opening near the connection means.

29. The first catheter assembly of claim 28 wherein the first opening in
the shaft and the first opening in the reverse facing segment allow a
bifurcated guidewire to move freely within the catheter.

30. The first catheter assembly of claim 25 further comprising a
deployment line positioned in the shaft.

31. The first catheter assembly of claim 30 wherein the deployment line is
attached or integral to a constraining sheath.

32. The first catheter assembly of claim 31 wherein the deployment line
exits the reverse facing segment and enters the shaft.

Description:

CROSS REFERENCE TO RELATED APPLICATIONS

[0001]This application is a continuation of co-pending and commonly owned
U.S. Ser. No. 11/474,165, filed on Jun. 23, 2006.

BACKGROUND OF THE INVENTION

[0002]The present invention generally relates to a delivery system and
method for delivering an expandable endoluminal prosthetic device such as
a stent graft and more particularly to a device and method for placing an
acutely angled bifurcated stent graft through a single access incision.
Expandable surgical devices such as stents or stent grafts are used in a
variety of places in the human body to repair aneurysms and to support
various anatomical lumens, such as blood vessels, respiratory ducts,
gastrointestinal ducts, and the like.

[0003]Conventionally, these devices are deployed across an aneurysm or in
the regions of a stenosis in the target body lumen to repair the aneurysm
or to hold the lumen open. Because stent graft implantation is a
relatively non-invasive procedure, it has been proven to be a favorable
alternative to surgery in, for example, the repair of an aneurysm.
Bifurcated devices with their trunk and branching configuration are
particularly well suited for use in branching body lumen systems, such as
in the coronary vasculature, and the peripheral vasculature. The coronary
vasculature includes the right, left common, left anterior descending and
circumflex arteries and their branches. The peripheral vasculature
includes branches of the carotids, aorta, femoral, popliteal, internal
iliac, or hypergastric and related arteries. Placement of such a
bifurcated device can be rather complicated, and often involves
approaching the bifurcated section of the artery through at least two
side branches or through the trunk plus one side branch. The procedure is
not only time consuming, but can also lead to more incision sites in the
patient's body and can necessitate more complicated maneuvers for the
surgeon. These complications are further exaggerated when an acutely
angled or reverse direction side branch is accessed, as for example a
repair of the hyporgastric artery. U.S. Pat. No. 6,645,242 teaches a
bifurcated intravascular stent graft comprising primary stent segments
and a primary graft sleeve forming a main fluid channel and having a side
opening therethrough.

[0004]However, there exists a need for a stent graft delivery system which
would allow placement of bifurcated stent grafts into acutely angled
vasculature such that simpler surgical procedures are enabled. A
simplified surgical procedure would decrease the number or size of
incisions, reduce the required surgical steps, and thereby reduce patient
trauma associated with a more complex medical procedure.

SUMMARY OF THE INVENTION

[0005]The present invention further provides an interventional delivery
system comprising: a first catheter having at its distal end a side
branch vessel segment; a second catheter attached around the first
catheter and having at its distal end a main vessel segment; and a side
branch vessel device attached to the side branch vessel segment of the
first catheter wherein the main vessel segment and the side branch vessel
device are simultaneously delivered to a treatment site, and further
wherein the second catheter has an opening in a side wall near the distal
end of the second catheter to allow for passage of the side branch vessel
segment of the first catheter. The second catheter may comprise a capture
tube which surrounds the bifurcated guidewire and facilitates for the
ease of bifurcated guidewire removal from a vessel. A bifurcated
guidewire with at least two distal tips may be used with the first
catheter. The two distal tips face opposing directions, wherein one of
the two distal tips is the leading end and one of the tips is a reverse
facing tip end.

[0006]The present invention further provides a first catheter having at
its distal end a side branch vessel segment; a second catheter attached
around the first catheter and having at its distal end a main vessel
segment; a side branch vessel device attached to the side branch vessel
segment of the first catheter; and a main vessel device attached to the
main vessel segment of the second catheter. The main vessel device and
the side branch vessel device are simultaneously delivered to a treatment
site.

[0007]A method of deploying a branched stent assembly is also provided
comprising: advancing a catheter assembly on a bifurcated guidewire to a
treatment site; orienting the catheter assembly in the main vessel;
pulling the bifurcated guidewire to orient the guidewire reverse facing
tip into the side branch vessel; deploying the main vessel device in the
main vessel; then advancing the side branch vessel device to a desired
location; and deploying the side branch device. After stent deployment,
removal of the delivery assembly is facilitated by advancing the
guidewire and first catheter forward until the guidewire reverse facing
tip and reverse facing portion of the first catheter are retracted from
the side branch vessel allowing removal of the bifurcated guidewire along
with the first and second catheters.

DESCRIPTION OF THE DRAWINGS

[0008]FIG. 1 shows the interventional delivery system comprising a first
catheter and a second catheter upon insertion in a vessel.

[0009]FIGS. 2A and 2B show the first catheter of the interventional
delivery system. FIG. 2A depicts a bent shaft configuration and FIG. 2B
depicts a shaft configuration using a connector.

[0010]FIG. 3 shows the bifurcated guidewire assembly with a leading
segment and a reverse facing segment.

[0011]FIG. 4A shows a first catheter with a bent shaft and apex opening
for the bifurcated guidewire with a side branch device mounted on the
side branch vessel segment of the first catheter shaft.

[0012]FIG. 4B shows a first catheter with a shaft configuration using a
connector for the bifurcated guidewire with a side branch device mounted
on the side branch vessel segment of the first catheter shaft.

[0013]FIG. 5 shows an enlarged view of the side branch vessel segment with
a side branch vessel device mounted and constrained within a sheath.

[0014]FIGS. 6A and 6B show side views of a second catheter with a side
branch opening.

[0015]FIG. 7 is an isometric view of an expanded main body stent graft.

[0016]FIG. 8 is a partial cross-sectional view of a main body stent with a
bifurcated guidewire and a first catheter with a side branch device.

[0017]FIG. 9 is a partial cross-sectional view of a main body stent with a
bifurcated guidewire and a first catheter with a side branch device
contained in a second catheter. Also shown is a constraint sheath over
the main body stent and the apertures in the main body stent and the
constraining sheath.

[0018]FIGS. 10A and 10B show partial cross-sectional views of the distal
device portion and the proximal hub portions of the interventional
delivery system of the present invention. The distal device portion is
positioned within a main vessel adjacent to a branched vessel.

[0019]FIGS. 11A and 11B show partial cross-sectional views of the distal
device portion and the proximal hub portions of the interventional
delivery system of the present invention. The reverse facing guidewire is
shown being advanced into the side branch, acutely angled vessel.

[0020]FIGS. 12A and 12B show partial cross-sectional views of the distal
device portion and the proximal hub portions of the interventional
delivery system of the present invention. The main body stent is shown in
an expanded state.

[0021]FIGS. 13A and 13B show partial cross-sectional views of the distal
device portion and the proximal hub portions of the interventional
delivery system of the present invention. The reverse facing segment of
the first catheter with a constrained side branch device is shown being
advanced into the side branch, acutely angled vessel.

[0022]FIGS. 14A and 14B show partial cross-sectional views of the distal
device portion and the proximal hub portions of the interventional
delivery system of the present invention. The side branch stent is shown
in an expanded state.

[0023]FIGS. 15A and 15B show partial cross-sectional views of the distal
device portion and the proximal hub portions of the interventional
delivery system of the present invention. The reverse facing portion of
the first catheter and the guidwire are shown being advanced into a
capture tube.

[0024]FIGS. 16A and 16B show partial cross-sectional views of the distal
device portion and the proximal hub portions of the interventional
delivery system of the present invention. The first catheter, the second
catheter, and the guidewire are shown being withdrawn from the treatment
site.

DETAILED DESCRIPTION OF THE INVENTION

[0025]The present invention provides an interventional delivery system for
the placement of bifurcated stent grafts into acutely angled vasculature.
Acutely angled vasculature may exist in renal vessels, subclavian
arteries, biliary ducts, prostate vessels, and other non-vascular
applications as well. The challenge in stent placement is deployment from
a main vessel such as a femoral artery to a reverse acute angle vessel.
The present invention provides a device and procedure which decreases the
number and size of incisions required to place bifurcated stent grafts
into acutely angled vasculature, and further reduces the required
surgical steps and patient trauma associated with this traditionally more
complex medical procedure. As shown in FIG. 1, the present invention
provides an interventional delivery system 30 comprising a first catheter
shaft 32, a second catheter assembly 34A or 34B, a first catheter hub
assembly 36, a second catheter hub assembly 38, a bifurcated guidewire
leading tip 40, a bifurcated guidewire reverse facing tip 42, a
bifurcated guidewire proximal tip 44, and a device assembly 46. The
interventional delivery system 30 is shown positioned in an anatomical
main vessel 48 so that the device assembly 46 is positioned approximate
to an anatomical side branch vessel 50. As described in subsequent
figures, the device assembly 46 will be deployed to form a main body
stent within the main vessel 48 along with an integrated side branch
stent within the side branch vessel 50.

[0026]Shown in FIGS. 2 through 9 are various sub-components and assemblies
of the interventional delivery system 30 (of FIG. 1). Shown in FIG. 2A is
a first catheter assembly 52A having a first catheter hub assembly 36.
The hub assembly 36 includes a perfusion port 54, a bifurcated guidewire
port 56, a side branch deployment line 58 protruding from a deployment
line port 60. The first catheter assembly 52A further comprises a first
catheter shaft 32 that has an apex opening 62A. Apex opening 62A as shown
is a cut-opening through the wall of the first catheter shaft 32. The
first catheter shaft is shown bent about the apex opening 62A, forming a
reverse facing segment 64. The reverse facing segment 64 has a side
branch device portion 66 and a side branch device to apex opening
separation length 68.

[0027]As shown in FIG. 2B a first catheter assembly 52B has a first
catheter hub assembly 36. The hub assembly 36 includes a perfusion port
54, a bifurcated guidewire port 56, a side branch deployment line 58
protruding from a deployment line port 60. The first catheter assembly
52B further comprises a first catheter shaft 32 that has an apex opening
62B. Apex opening 62B as shown comprises the open ends of a cut catheter
shaft 32. The two cut ends are joined at connection 70. The two cut
shafts as shown form a reverse facing segment 64. The reverse facing
segment 64 has a side branch device portion 66 and a side branch device
to apex opening separation length 68.

[0028]Depicted in FIG. 3 is a bifurcated guidewire assembly 72 having a
proximal tip and a main segment 76. Within the distal portion of the
guidewire main segment 76 is a connection 78, defining a leading
guidewire segment 80 and a reverse facing guidewire segment 82. The
leading guidewire segment has a leading tip and the reverse facing
guidewire segment has a reverse facing tip.

[0029]FIG. 4A shows a first catheter assembly (52A of FIG. 2A) combined
with a bifurcated guidewire assembly (72 of FIG. 3). Referring to FIGS.
2A, 3, and 4A, shown is a bifurcated guidewire assembly 72 positioned
within a first catheter assembly 52A. Shown protruding from an apex
opening 62A is the bifurcated guidewire connection 78 along with the
leading guidewire segment 80. The proximal end of the bifurcated
guidewire protrudes from the bifurcated guidewire port 56 and the reverse
facing tip of the guidewire protrudes from the reverse facing segment of
the first catheter.

[0030]Similarly, FIG. 4B shows a preferred first catheter assembly (52B of
FIG. 2B) combined with a bifurcated guidewire assembly (72 of FIG. 3).
Referring to FIGS. 2B, 3, and 4B, shown is a bifurcated guidewire
assembly 72 positioned within a first catheter assembly 52B. Shown
protruding from an apex opening 62B is the bifurcated guidewire
connection 78 along with the leading guidewire segment 80. The proximal
end of the bifurcated guidewire protrudes from the bifurcated guidewire
port 56, and the reverse facing tip of the guidewire protrudes from the
reverse facing segment of the first catheter. The tube-to-tube connection
70 can include a friction-reducing component or feature to allow the
deployment line 58 to easily slide against the tubes or apex opening as
the deployment line is activated.

[0031]Shown in FIG. 5 are a partial cross-sectional view of the reverse
facing segment 64 that includes a side branch device portion 66 and a
side branch device to apex opening separation length 68. Shown is the
bifurcated guidewire 72 reverse facing tip 42 exiting from an olive 88.
Positioned onto a side branch accommodating segment 94 is a constrained,
self-expanding side branch device 90. The side branch device 90 is held
in a compressed state by a constraining sheath 92. Attached or integral
to the constraining sheath is a side branch device deployment line 58.

[0032]FIGS. 6A and 6B are side views of two embodiments of a second
catheter. Shown in FIG. 6A is a second catheter assembly 34A having a
second catheter hub assembly 38. The second catheter hub assembly further
includes a proximal perfusion port 54. The hub assembly is joined to a
second catheter main body 96. Near the distal end of the second catheter
main body 96 is a side branch device opening 98, formed by a cut-out
portion of the catheter wall. The opening 98 allows a bifurcated
guidewire and a side branch device to be subsequently advanced from the
second catheter. After deployment, the bifurcated guidewire can be pulled
through the opening 98 into the second catheter for removal. At the
distal end of the second catheter main body is a capture tube portion
100. This tube portion "captures" the bifurcated guidewire after device
deployment, allowing for a non-traumatic removal of the guidewire and
delivery system.

[0033]Similarly, FIG. 6B depicts an alternate embodiment of a second
catheter assembly 34B. The distal end of the second catheter main body 96
is joined to the capture tube portion 100 by at least one main body to
capture tube joining member 102. The main body 96 and the capture tube
102 are therefore separated and connected by the joining members 102. The
gap between the main body and the capture tube forms an opening 98
functionally similar to the opening 98 shown in FIG. 6A.

[0034]FIG. 7 is an isometric view of an expanded main body device 104. An
aperture 106 is formed in the main body device wall, permitting a side
branch device to be subsequently inserted through and attached to the
aperture/main body.

[0035]FIG. 8 is a partial cross-sectional view of a main body device 104
surrounding a first catheter assembly 52B. A bifurcated guidewire 72 is
positioned within the first catheter (as previously shown in FIG. 4B). A
reverse facing portion of the first catheter having a constrained side
branch device is shown protruding through an aperture 106 in the main
body stent. Exiting from the reverse facing portion of the first catheter
is the reverse facing tip 42 of the bifurcated guidewire. Also shown are
the first catheter shaft 32 and the apex opening 62B.

[0036]FIG. 9 is a partial cross-sectional view of the components depicted
in previous FIG. 8 along with a second catheter 34B (refer to FIG. 6B).
Shown is a second catheter main body 96, connected to a capture tube
portion 100 by at least one joining member 102. The distal end of the
bifurcated guidewire is shown positioned within the capture tube portion
100. The first catheter shaft 32 is shown positioned within the second
catheter main body 96. Also shown are a constraining sheath 92 and the
attached or integral main body deployment line 109. The reverse facing
portion of the first catheter is shown protruding through an aperture 108
within the constraining sheath 92.

[0037]A sequence used to deliver and deploy main body and side branch
stents according to the present invention is depicted in FIGS. 10 through
16.

Deployment Step 1

[0038]FIG. 10A is a partial cross-sectional view of the distal end of an
interventional delivery system similar to that of FIG. 1. A device
assembly is shown initially positioned in an anatomical main vessel 48 so
that the device assembly is positioned approximate to an anatomical side
branch vessel 50. Shown are a bifurcated guidewire leading tip 40 and a
bifurcated guidewire reverse facing tip 42. The device assembly (46 of
FIG. 1) has been expanded to display the internal components as shown in
FIG. 9. FIG. 10B depicts the proximal end of the interventional delivery
system, similar to that shown in FIG. 1. Shown are a first catheter hub
assembly 36 and a second catheter hub assembly 38.

Deployment Step 2

[0039]FIGS. 11A and 11B show the bifurcated guidewire reverse facing tip
42 being advanced into the side branch vessel 50 along the direction
indicated by arrow 110. The guidewire reverse facing tip 42 is advanced
by pulling (in direction indicated by arrow 112) on the proximal end of
the guidewire. The two hub assemblies 36, 38 are held stationary as the
proximal end of the guidewire is pulled. As the proximal end of the
guidewire is pulled, the guidewire leading tip 40 is advanced towards the
apex opening 62B in the direction shown by arrow 114. The guidewire
reverse facing tip 42 is therefore forced to advance into the side branch
vessel 50 in the direction of arrow 110.

Deployment Step 3

[0040]Referring to FIGS. 12A and 12B, the main body stent 104 is deployed
by pulling on the main body stent deployment line 109 in the direction
indicated by arrow 116. By releasing the constraining sheath (92 of FIG.
9) the main body stent is allowed to self-expand in the directions
indicated by arrows 118. The two hub assemblies 36, 38 are held
stationary as the deployment line is pulled. Note that the guidewire
and/or the side branch device are positioned through the aperture 106 in
the main body device 104.

Deployment Step 4

[0041]The side branch device is then advanced into the side branch vessel,
as depicted in FIGS. 13A and 13B. The side branch device is advanced
along the direction indicated by arrow 120 by holding stationary the
second catheter hub assembly 38 while concurrently pulling on the
guidewire proximal tip 44 and the first catheter hub assembly 36. The
guidewire may be optionally locked onto the first catheter hub assembly
36 to facilitate this step. As the guidewire and hub assembly are pulled,
the distal tip of the guidewire 40 is pulled in the direction indicated
by arrow 124, forcing the side branch device to advance partially through
the main body device aperture 106 and into the side branch vasculature 50
in the direction 120.

Deployment Step 5

[0042]As shown in FIGS. 14A and 14B, the side branch deployment line 58 is
then pulled in the direction indicated by arrow 126, allowing the side
branch device 66 to self-expand as indicated by arrows 128. Note that the
side branch device is partially contained within and constrained by the
main body device aperture 106. The two hub assemblies 36, 38 are held
stationary as the deployment line is pulled.

Deployment Step 6

[0043]Referring to FIGS. 15A and 15B, the delivery system of the present
invention is withdrawn from the vasculature by forcing the reverse facing
portion of the first catheter 64 out of the expanded side branch device
and into the capture tube 100 along the direction as indicated by arrows
130. The first catheter reverse facing portion is driven, into the
capture tube by pushing the first catheter hub assembly 36 along with the
guidewire proximal tip 44 along the direction as shown by arrows 132. The
second catheter hub assembly 38 is held stationary as the first catheter
hub assembly and the guidewire are advanced.

Deployment Step 7

[0044]To complete the delivery of the devices and systems of the present
invention, the first catheter hub assembly 36, the guidewire proximal tip
44, and the second catheter hub assembly 38 are concurrently pulled in
the direction as shown by arrows 134 of FIGS. 16A and 16B. The capture
tube 100, containing the bifurcated guidewire and the reverse facing
portion or the first catheter 64 are non-traumatically removed from the
vasculature, leaving the expanded main body device 104 and the attached
side branch device 66 in the vasculature.

[0045]Referring back to FIG. 7, the main body device 104 is shown with a
single side-wall aperture 106. In an alternate configuration, a main body
device can have two, three, four, five, six or more side branch
apertures. The various catheters of the present invention can incorporate
more than one device; for example, a first catheter can incorporate two
or more side branch devices. The sealing or interference fit between a
main body and a side branch device can be enhanced by the incorporation
of a "sealing sleeve". See for example U.S. Pat. No. 6,645,242 to Quinn
for a disclosure of such sealing sleeves. Multiple sealing sleeves can be
incorporated into a main body device to enhance the sealing or attachment
of multiple side branch devices. Sealing sleeves can be "internal to" or
"external to" the lumen of a main body stent and can be shaped and sized
to seal a specifically configured side branch device.

[0046]Stents used in the present invention can be bare (uncovered), coated
with a variety of drug eluting, anti-thrombogenic or other coatings, or
can include a partial or full cover (as in a stent graft). Anchoring
mechanisms, such as barbs, "fish-scales", biological attachment means, or
other features can be incorporated into the main body and/or a side
branch device to facilitate anchoring to the vasculature.

[0047]Main body stents and/or side branch stents can have a uniform
profile or have non-uniform profiles such as tapers, "trumpet-end"
shapes, "dog-bone" shapes, curves or other profiles that enhance the
device performance within a particular treatment site. Multiple devices
of the present invention can be "ganged" or interconnected to form a
multi-component system. Devices of the present invention can include
features that allow or enhance the interconnection or "docking" between
multiple devices.

[0048]Radiopaque markers or indicators can be incorporated into a main
body device, the various catheters used in the present invention and/or a
side branch device to facilitate placement and visualization within the
vasculature.

[0049]Devices of the present invention can be used to treat non-vascular
conduits, hollow or tubular parts of organs, such as bilary, bladder,
urethra, gastrological, bronchi, bile, and other ducts. Devices of the
present invention are particularly suited for, but not limited to, side
branch vessels that have an "acute" angle from the main body (see for
example FIG. 1).

[0050]Devices of the present invention can be balloon-expandable as well
as self-expanding. For example, the first catheter according to the
present invention can incorporate a balloon (or balloons) and inflation
lumens as required to expand a particular device. Combinations of
self-expanding and balloon-expandable devices can be configured according
to the present invention. Also, separate balloon expanders can be used
within the scope of the present invention.

[0051]Catheter components of the present invention can be fabricated from
common materials such as nylons, polycarbonates, polyethylenes,
polypropylenes, polytetrafluoroethylenes, polyvinyl chlorides,
polyurethanes, polysiloxanes, stainless steels, nitinols, or other
biocompatible materials.

[0052]While particular embodiments of the present invention have been
illustrated and described herein, the present invention should not be
limited to such illustrations and descriptions. It should be apparent
that changes and modifications may be incorporated and embodied as part
of the present invention within the scope of the following claims.